Buffalo Burger with Bourbon Glazed Onions

Name: Buffalo Burger with Bourbon Glazed Onions
Prep time: 20 min
Cook time: 1 h 10 min
Total time: 1 h 10 min
Yield: 4 portions
Ingredients: 6 - 8 fresh sage leaves; 2 ½ oz shallots; 1 garlic clove; 1 tsp mustard powder; &frac18; tsp freshly ground black pepper; 16 oz ground buffalo meat; 18 oz red onions; ½ oz olive oil; ½ oz unsalted butter; 2 oz dark brown sugar; ¼ tsp salt; ¼ tsp ground black pepper; 2 oz bourbon; salt; 4 hamburger buns; ketchup; 4 slices cheddar cheese; 4 oz Roma tomatoes; 4 - 8 pieces butter lettuce